Buchi DuMaster D-480, Руководство по эксплуатации

Страница: 171 / 354

Operating instructions DuMaster D-480 ©BÜCHI Labortechnik AG
8 - Maintaining the instrument 171
Flushing tubes
Requirements:

A new tube has been installed.

The analyzer is in "Replace part" status.

The tube ends are closed.
Safety instruction
Strictly observe the safety instruction "Gas pressure" under
Warning notes during operation
(on
page 24).
Proceed as follows:

Close the "Replace part" dialog in the operating software. To do so, click
Finish
in the "Replace
part" dialog. This automatically switches on the gas again and the atmospheric nitrogen is
removed by flushing with CO
2
.

Decide:
If the operating software status view displays...

... approximately the same flow and pressure values as prior to maintenance work are
displayed: The instrument is ready to measure again. Go to the next step.

... distinctly different flow and pressure values to those displayed prior to maintenance work
are displayed: Perform a leak test. See Performing a leak test. Only move on to the next
step once the leak test is successful.

Performing blank value determinations. See
Determining blank values
(on page 141). Allocate
the method "Blank with O2" to the samples.

Only stop blank value determination when the N blank value is stable and small. See "Measure of
gas-tightness" in Types of blank value determination and their settings. The instrument is then
ready to measure again.
Conditioning combustion tube, post combustion tube and Reductor
The following tables explains conditioning rules for the various modes:
Mode Reaction tube Conditioning rule
N

Combustion tube

Post combustion tube

Reductor

Bake out at working temperature for 15
minutes.

Conditioning when replacing.

Conditioning when replacing.
Heat out combustion tube, post combustion tube
Requirements:

A new combustion tube, post conbustion tube and/or Reductor has been installed.

The tube ends must be open. For this,...

... the quartz glass bridge must not be attached to the end of the combustion tube.

... the ground joint must not be clipped onto the end of the post combustion tube.
Safety instruction
Strictly observe the safety instruction "Baking out combustion and reduction tube" under
Warning
notes during operation
(on page 24).
Proceed as follows: